Jul 14 2026
RestaurantsKid Shelleen's - Trolley SquareFrench Onion Gratin Recipe

French Onion Gratin Recipe

Time1h 30m
Serves4

CUP

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Ingredients

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Main Ingredients

Method

Preparation

  1. 1

    Caramelize the Onions

    In a large, heavy-bottomed pot, melt the butter and olive oil over medium heat. Add the sliced onions and stir to coat them in the fat. Cook, stirring occasionally, for about 30-40 minutes until the onions are caramelized and golden brown.

  2. 2

    Deglaze the Pot

    Once the onions are caramelized, add the dry white wine to the pot. Scrape the bottom of the pot with a wooden spoon to deglaze, allowing the wine to evaporate slightly, about 5 minutes.

  3. 3

    Add Broth and Seasonings

    Stir in the beef broth, thyme, bay leaves, salt, and black pepper. Bring the mixture to a simmer and let it cook for an additional 20 minutes to blend the flavors.

  4. 4

    Preheat the Oven

    While the soup is simmering, preheat your oven to 375°F (190°C).

  5. 5

    Prepare the Baguette

    Slice the baguette into 1-inch thick pieces. Arrange the slices on a baking sheet and toast them in the preheated oven for about 10 minutes until golden brown.

  6. 6

    Assemble the Gratin

    Ladle the soup into oven-safe bowls. Place a slice or two of toasted baguette on top of each bowl, then sprinkle generously with Gruyère and Parmesan cheese.

  7. 7

    Bake

    Transfer the assembled bowls to the oven and bake for 15-20 minutes, or until the cheese is bubbly and golden brown.

  8. 8

    Serve

    Remove from the oven, let cool for a few minutes, and serve hot. Enjoy your delicious French Onion Gratin!

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